Lumbar intraspinal synovial and ganglion cysts (facet cysts). Ten-year experience in evaluation and treatment

A challenge diagnosis of lumbar synovial facet cyst. A case report

INTRODUCTION AND IMPORTANCE

Synovial cysts occur more frequently in the lumbar spine, especially at L4-5 level. Traditional open surgical management with posterolateral arthrodesis is the currently recommended treatment.

CASE PRESENTATION

This is a 64-year-old woman with no prior pathological history. Initial clinical and radiological assessment concluded that there was advanced right coxarthrosis with a degenerative lumbar spine. The patient therefore had a total hip arthroplasty secondarily presented an intermittent neurogenic claudication without sphincter disorders. The MRI concluded at a compressive synovial facet cyst at the L4-L5 level. The patient underwent surgical treatment. At two years postoperatively, the walking distance was significantly improved while maintaining moderate lower back pain.

CLINICAL DISCUSSION

The diagnosis of synovial facet cysts of spine is a challenge that depends heavily on history, physical examination, and MRI. MRI will demonstrate not only the nature of the cystic lesion, but also its relationship to the root, the cord or the thecal sac. The L4-L5 level of the lumbar spine is the most common location of the synovial cyst of the facet joints. As in our case, surgical treatment combining posterolateral arthrodesis is currently recommended for these types of lesions. Surgical treatment, as in our case, is sometimes delayed when this pathology is associated with advanced osteoarthritis of the hips.

CONCLUSION

Improved imaging capabilities such as magnetic resonance imaging (MRI) have resulted in increased reporting, diagnostic yield and treatment of spinal synovial cysts. Surgical treatment combining posterolateral arthrodesis is the treatment for this lesion.

Cysts of the ligamentum flavum are often linked to ischemic conditions: A morphological study

"Cysts of the ligamentum flavum (cysts-LF)" is the term for non-neoplastic cystic lesion involving LF. The aim of the present study was to elucidate the histopathological characteristics and pathogenesis of "cysts-LF". Herein, we defined cysts-LF as spinal cysts containing degenerative LF components. From archival cases, we investigated 18 symptomatic cysts-LF surgically removed from 18 patients (13 males and five females; median age 68.5 years [range, 42-86 years]). The elastic fibers of LF components in the wall were separated and/or torn, and cyst walls were accompanied by chondroid metaplasia (17 cases), myxoid changes (13 cases), ossification (11 cases), amyloid deposits (14 cases), hemosiderosis (six cases), granular/smudgy calcification (four cases), synovial cell linings (three cases), and severe inflammatory infiltrates (one case). These histologic features of our cysts-LF were shared by previously reported "cysts-LF." Fourteen cysts-LF demonstrated vascular stenosis/occlusion, and eight showed thick hyalinized vessels, suggesting local circulatory insufficiency. Eight cases (44%) exhibited lipomembranous fat necrosis, accompanied by hyalinized vascular changes (p = 0.003). Ischemic conditions were observed in nearly half of the present cysts-LF, and may be one of the main contributing factors for the formation of cysts-LF, via degeneration and cystic changes in the LF.

Evolution of lumbar degenerative spondylolisthesis with key radiographic features

Spondylolisthesis is a common finding in middle-aged and older adults with back pain. The pathophysiology of degenerative spondylolisthesis is a subject of controversy regarding not only its etiology but also the mechanisms of its progression. It is theorized that degeneration of the facets and discs can lead to segmental instability, leading to displacement over time. Kirkaldy-Willis divided degenerative spondylolisthesis into three phases: dysfunction, instability, and finally, restabilization. There is a paucity of literature on the unification of the radiological hallmarks seen in spondylolisthesis within these phases. The radiographic features include (1) facet morphology/arthropathy, (2) facet effusion, (3) facet vacuum, (4) synovial cyst, (5) interspinous ligament bursitis, and (6) vacuum disc as markers of dysfunction, instability, and/or restabilization. We discuss these features, which can be seen on X-ray, CT, and MRI, with the intention of establishing a timeline upon which they present clinically. Spondylolisthesis is initiated as either degeneration of the intervertebral disc or facet joints. Early degeneration can be seen as facet vacuum without considerable arthropathy. As the vertebral segment becomes increasingly dynamic, fluid accumulates within the facet joint space. Further degeneration will lead to the advancement of facet arthropathy, degenerative disc disease, and posterior ligamentous complex pathology. Facet effusion can eventually be replaced with a vacuum in severe facet osteoarthritis. Intervertebral disc vacuum continues to accumulate with further cleft formation and degeneration. Ultimately, autofusion of the vertebra at the facets and endplates can be observed. With this review, we hope to increase awareness of these radiographical markers and their timeline, thus placing them within the framework of the currently accepted model of degenerative spondylolisthesis, to help guide future research and to help refine management guidelines.

Recognition of Prodromal Hypoglossal Nerve Palsy Presenting with Neck Pain as Primary Complaint: Findings from a Rare Case Report in Direct Access Physiotherapy during the COVID-19 Pandemic

Neck pain (NP) is the second most common musculoskeletal disorder. Spinal cysts (SCs) are cystic dilatations of the synovial sheaths in joints and tendons. SCs are extremely rare in the cervical spine. Typically, patients are unaware of having an SC due to its asymptomatic nature; however, when cervical SC extends, its volume could compress the surrounding structures, such as the hypoglossal nerve. Isolated hypoglossal nerve palsy (HNP) is very rare and typically presents with unilateral atrophy of the musculature of the tongue and contralateral tongue deviation. Often, patients with HNP also report occipital/neck pain. A 75-year-old man with occipital/neck pain as a primary complaint. Although difficult to observe because of the filtering facepiece two mask, difficulties in articulation and sialorrhea during the interview were noticed. These latter were cues to consider CN examination that revealed CN XII palsy. This prompted a referral for further examination that revealed an SC compressing the right hypoglossal canal. The patient was not considered a surgical candidate and was managed conservatively. This case report outlines the relevant findings relating to the triage of a rare isolated hypoglossal nerve palsy from the physiotherapist's perspective within a complex setting because of the COVID-19 pandemic. Although referred with a diagnosis of cervical radiculopathy, our case highlights that skilled physiotherapists may play a fundamental role in both the recognition and, when applicable, subsequent novel management of a non-musculoskeletal presentation.

Effectiveness and Safety of CT-Guided Facet Joint Cyst Rupture for Radicular Pain as First Choice Therapy: A Retrospective Analysis

OBJECTIVE

To evaluate effectiveness and safety of computed tomography (CT)-guided cyst rupture with intraarticular contrast-enhanced injection of steroid and local anesthetic as first choice therapy in patients with facet joint cyst-induced radicular pain.

DESIGN

Retrospective data set analysis.

SETTING

University hospital.

SUBJECTS

One hundred and twenty-one patients suffering from radicular pain attributable to facet joint cysts were included.

METHODS

The rate of patients without following surgery was assessed and defined as surrogate to measure effectiveness. Patients' characteristics, procedure-associated complications, technical aspects, and imaging findings on magnetic resonance imaging (MRI) were analyzed. A subgroup of 65 patients (54%) underwent telephone interview to assess pain relief and clinical outcome measured by Numeric Rating Scale and Oswestry Disability Index. Analyses between the groups with and without surgery were performed by Fisher exact test and two-sample unpaired t-test, respectively.

RESULTS

The effectiveness of CT-guided cyst rupture was found to be 66.1%. Procedure-induced pain yielded in premature abort in two cases (1.7%). The detection of epidural contrast agent was statistically significantly associated with no need for surgery (P = .010). The cyst level was associated with the status of following surgery (P = .026), that is, cysts at lower lumbar spine were easier to rupture than cysts at other locations (cervical, thoracic, or upper lumbar spine). No further significant association was found.

CONCLUSIONS

CT-guided cyst rupture as the first-choice therapy in patients with cyst-induced radicular pain was safe and effective. Successful cyst rupture was associated with no need for surgery. Cysts at lower lumbar spine revealed the highest success rate.

Efficacy of Percutaneous Image-Guided Rupture of Lumbar Facet Cysts: A Retrospective Study

Background

Percutaneous rupture of lumbar facet cysts (LFC) is the only nonsurgical treatment which is effective in directly reducing cysts. However, this is not yet a common procedure, and its effectiveness, including the associated complications, remains unclear. Therefore, this study aimed to evaluate the clinical outcomes of percutaneous rupture for LFC and elucidate whether this minimally invasive procedure could become an alternative to surgeries for cases resistant to conservative treatments.

Methods

This study investigated 57 symptomatic patients with LFC for whom conservative treatments were ineffective and underwent percutaneous rupture of the LFC. All patients were followed up for >2 years posttreatment. Clinical evaluations (visual analogue scale (VAS) and recovery rate calculated using the Japanese Orthopedic Association (JOA) scores) and radiographic evaluations (size of LFC based on magnetic resonance imaging (MRI)) were performed from pretreatment to the final follow-up examination.

Results

Successful LFC rupture, without hospitalization and general anesthesia, was achieved in 48 patients. No severe complications occurred during treatment through the last observation. Satisfactory clinical results with significant improvements in the VAS and JOA scores were obtained (VAS: pre/posttreatment: 80.7 mm/11.2 mm, JOA: pre/posttreatment: 15.6 points/26.7 points, and recovery rate: 82.3%). A significant reduction in the LFC was also observed in all cases based on the posttreatment MRI findings. No successful rupture cases required subsequent surgical treatments, although four cases of LFC recurrence required additional percutaneous rupture treatment.

Conclusions

Percutaneous rupture for LFC is not only a safe and minimally invasive procedure without any severe complications or requirements for hospitalization and general anesthesia but also a beneficial procedure that can eliminate the need for surgery in cases resistant to conservative treatments.

High Rate of Revision Surgery After Limited Decompression of Lumbar Facet Cysts

INTRODUCTION

The surgical treatment of lumbar facet cysts has long been debated. Some surgeons elect for limited decompression of such cysts while other surgeons elect for primary decompression and fusion over concerns for recurrence and instability. Previous studies have suggested the rate of revision surgery after facet cyst excision to be as low as 1%, whereas others have reported this rate to be markedly higher. In this study, we examined revision surgery rates and patient-reported outcomes and conducted a radiographic analysis to identify predictors of failure after limited decompression of lumbar facet cysts.

METHODS

A retrospective review of the electronic medical records of patients treated at our institution using the Current Procedural Terminology code 63267 before January 2018 was conducted. The primary outcome measure was revision surgery at the index level for recurrence or instability or a minimum 2-year follow-up without revision surgery. Secondary outcome measures include radiographic assessments of preoperative and postoperative spondylolisthesis and patient-reported outcome measures. Using preoperative MRI studies, an analysis of facet angles at the surgical level was conducted and the presence, location, and amount of facet fluid were calculated.

RESULTS

A total of 162 patients met inclusion criteria. Of these, 93 patients had a minimum 2-year follow-up. Of these, 19 had undergone a revision surgery at the index level for cyst recurrence or instability. The revision rate for this group was 20.4%. The median time to initial revision surgery was 2.2 years. The median time from index operation to last follow-up was 3.8 years. No differences were observed between the groups regarding the presence of preoperative spondylolisthesis, age, sex, body mass index, blood loss, or patient demographics. 60.2% of all procedures were done at the L4-5 level, but this level accounted for 73.7% of primary failures. A radiographic analysis showed facet angle >45° at L4-5 to be associated with risk of failure of primary decompression. The presence and absolute amount of fluid in the facets were not associated with risk of failure at the L4-5 level.

DISCUSSION

Our revision rate of 20.4% is higher than what is commonly reported in the literature. The radiographic analysis shows that at the L4-5 level, a facet angle of >45° is associated with failure of primary decompression.

Acute development of spinal lumbar synovial facet cyst within 1 week after lumbar decompression: illustrative case

BACKGROUND

Synovial facet cysts can sometimes develop in patients with lumbar spinal stenosis after decompressive laminectomy. The etiology of spinal lumbar synovial cysts is still unclear, but their formation is associated with underlying spinal instability, facet joint arthropathy, and degenerative spondylolisthesis.

OBSERVATIONS

A 61-year-old-male patient presented with neurogenic claudication due to lumbar spinal stenosis. Radiographic studies showed grade I spondylolisthesis and radiological predictors of delayed spinal instability. He underwent lumbar decompression and shortly thereafter developed spinal instability and recurrent symptoms, with formation of a new spinal lumbar synovial facet cyst. He required revisional decompression, cyst excision, and posterolateral spinal fusion for definitive treatment.

LESSONS

The literature reports postoperative spinal instability in up to one-third of patients with lumbar spinal stenosis and stable degenerative spondylolisthesis who undergo decompressive laminectomy. Close radiographic monitoring and early advanced imaging may be prudent in this patient population if they develop new postoperative neurological symptoms and show radiographic predictors of instability on preoperative imaging. Posterolateral spinal fusion with instrumentation should be considered in addition to lumbar decompression in this select group of patients who demonstrate radiographic predictors of delayed spinal instability if they are medically capable of tolerating a spinal fusion procedure.

Lumbar spine abnormalities and facet joint angles in asymptomatic elite junior tennis players

BACKGROUND

Lumbar spine abnormalities, in particular stress fractures to the pars interarticularis, are common in elite junior tennis players, though the difference in prevalence between males and females remains unclear. Further, facet joint orientation appears to be a possible option for recognizing which players might go on to present with a pars stress fracture. Given the link between pars stress fractures and low back pain in tennis players, it appears logical to explore the link between facet joint angle and pars abnormalities. Thus, the purpose of this study was to describe the prevalence of lumbar spine abnormalities and explore the relationship between facet joint orientation and pars abnormalities in elite adolescent tennis players.

METHODOLOGY

Lumbar spine MRI images of 25 elite junior tennis players were obtained and distributed between five radiologists for analysis. Descriptive comparisons and confidence intervals were used to describe the prevalence of the abnormalities. A generalized linear regression model was conducted to investigate the relationship between lumbar pars abnormalities and lumbar facet joint angles.

RESULTS

Sixteen (64%) of 25 players were found to have at least one lumbar spine abnormality. Pars abnormalities affected 36% of players while bone marrow edema was found in 24% of players. Disc herniation, disc degeneration, and facet joint degeneration were diagnosed in 20%, 44%, and 24% of players respectively. Lastly, one player (4%) was diagnosed with spondylolisthesis. Females had significantly larger facet joint angles across L3/4 L5/S1 compared to males (p < 0.01). Further, those who had pars abnormalities had larger facet joint angles compared to those who did not (p < 0.001).

CONCLUSION

Disc degeneration, pars abnormalities, including bone marrow edema, and facet joint degeneration were common findings among elite adolescent tennis players. Additionally, this study is the first to discover that pars abnormalities are linked to facet joint angle in elite adolescent tennis players. This finding might assist in identifying tennis players at a greater risk of developing lumbar spine pars abnormalities in the future.

Rapid Spontaneous Resolution of Lumbar Intraspinal Facet Cyst after Lateral Lumbar Interbody Fusion

Introduction

Intraspinal facet cysts resistant to conservative treatment are treated surgically. Surgical treatment was generally resection and decompression, but complications of dural tear and recurrence sometimes occurred. We present good clinical results and rapid spontaneous resolution following treatment of five cases of lumbar intraspinal facet cyst after lateral lumbar interbody fusion (LLIF).

Methods

Multicenter series of five cases of lumbar intraspinal facet cyst with segmental instability treated with LLIF. The cross-sectional area (CSA) of the thecal sac and facet cyst on T2-weighted axial magnetic resonance imaging and the distance of facet joint (FJ) gap on axial computed tomography were measured preoperatively and postoperatively. Patient data and clinical and radiographic results were described.

Results

Of five patients, one was male and four were female, with an average age of 72.6 (61-76) years. The mean preoperative CSA of facet cyst was 40.09 mm². In all cases, intraspinal facet cyst resolved within two weeks after LLIF and good clinical results were obtained. The mean CSA of the thecal sac increased from 64.18 mm² preoperatively to 95.72 mm² postoperatively. The mean distance of FJ gap increased from 0.8 (0-1.5) mm preoperatively to 3.1 (0.5-6.0) mm postoperatively.

Conclusions

LLIF may be indicated for intraspinal facet cysts with segmental instability.

Hemorrhagic synovial cyst: An unexpected cause of acute cervical spinal cord compression. Case report

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Chronic inflammation of the synovial cyst induces neovascularization of its wall leading to a possible intra-cystic bleeding.

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The different signal modulations on MRI are due to the variable consistency and density of the cystic fluid.

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Synovial cyst hemorrhage produces a sudden increase in the size of the lesion with compression of the spinal cord and nerve roots.

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Surgery is the appropriate treatment in case of synovial cyst with spinal cord compression.

Introduction

Cervical synovial cysts are uncommon. They are most often responsible for a chronic clinical picture. Rarely, intracystic hemorrhage occurs, and may acutely present as radicular – or even spinal cord compression syndrome leading to irreversible neurological impairment.

Case

We reported a case of bleeding synovial cyst located in the cervico-thoracic spine causing spastic paraparesis in a 68-year-old male patient. MRI revealed narrowing of perimedullary subarachnoid space by a well circumscribed, extra-axial, homogeneous mass located posterolaterally to the right of the spinal cord at the level C7-T1. The cyst was removed thoroughly by laminectomy. Pathological findings were consistent with the diagnosis of hemorrhagic synovial cyst. The patient had an excellent recovery.

Discussion

Synovial cysts of the spine are rare and usually asymptomatic. It is extremely rare for intracystic bleeding to occur and be responsible for an abrupt presentation. Diagnosis of spinal synovial cyst relies on MRI but may not be evident as it depends on consistency and density of the cystic fluid.

Surgery remains the best therapeutic alternative, especially in the case of neurological impairment.

Conclusion

Surgery should be considered for any cervical synovial cyst. This is motivated by the risk, although rare, of bleeding and the resulting irreversible neurological damage that may occur.

Transdural Approach to Resection of Intraspinal Extradural Ventral Cysts in the Lumbar Spine

BACKGROUND

Intraspinal extradural ventral cysts in the lumbar spine can cause back pain and neurological deficits of the lower extremities. For the resection of this type of space-occupying lesion, the transdural approach has not been reported in the literature.

CASE DESCRIPTION

A 66-year-old man presented, suffering from progressive radiation pain of his bilateral lower extremities. Imaging examination revealed a cystic lesion in ventral side of lumbar spinal canal. We conducted the excision of the cyst with the transdural approach. The symptoms of the patient disappeared immediately after the operation and recurrence of the symptoms has not been observed in the 3-month follow-up.

CONCLUSIONS

This operation approach is safe and effective. Compared with the previous surgical approach reported in the literature, by this approach surgeons could achieve less injury, shorter operation time, and the same surgical outcomes in the short term. Therefore, we would like to present this approach to provide an alternative to deal with similar lesions.

Gas containing intraspinal synovial cyst in the lumbar spine: Case report and literature review

Intraspinal synovial cyst (ISC) is a well-documented pathology. It is sometimes found in the degenerative lumbar spine and can result in neurological disorders. ISC typically contains xanthochromic fluid, blood, inflammatory tissue, and/or osseous structures, enclosed by fibrous tissue. Regarding the treatment modalities, the effectiveness of both nonsurgical management, such as oral analgesics, needle aspiration, and intra-articular injection of corticosteroid drugs, and surgical management, have been reported. Previous studies have described that the ISC can contain gas, which is derived from the vacuum phenomenon of an adjacent facet joint; however, this clinical condition has never been systematically investigated because of its rarity. In the present report, we describe the case of a 68-year-old male with gas-containing ISC in the lumbar spine who was successfully treated with surgical management; additionally, we performed a literature review to discuss the decision-making process for cases of gas-containing ISC. Based on our findings and previous literature, we recommend that considering the peculiarity of the content of such lesions in addition to the ball-valve effect of a synovial cyst, prompt transition to surgical management would be pertinent when nonsurgical treatment cannot achieve satisfactory outcomes in such cases.

The Variability of Lumbar Facet Joint Synovial Cyst Recurrence Requiring Revision Surgery After Decompression-only and Decompression/Fusion

STUDY DESIGN

This is a retrospective study.

OBJECTIVE

The objective of this study was to evaluate lumbar spine synovial cyst recurrence rates of decompression-alone versus decompression/fusion procedures.

BACKGROUND

Improvements in imaging modalities allow for increased diagnosis and surgical treatment of symptomatic spinal juxtafacet synovial cysts. Conservative management may be used as a first-line management strategy, however rarely provides durable, effective relief of symptoms. Surgical treatment of spinal synovial cysts ranges from decompression and cyst excision to decompression with fusion procedures. Decompression procedures alone have a higher risk of recurrence of spinal synovial cysts.

METHODS

We retrospectively reviewed 87 patients undergoing surgical treatment of lumbar spinal juxtafacet synovial cysts as a single institution over 20 years. Surgical treatment consisted of either decompression versus decompression/fusion procedures. Preoperative symptoms included back pain, radiculopathy, motor deficits, or sensory deficits. The incidence of recurrence of spinal synovial cysts at the same-site or differing sites was compared between 2 categories of surgical treatment. Revision surgical procedure rates were also evaluated.

RESULTS

A total of 55 (63%) patients were treated with an index decompression-only procedure for the lumbar spinal synovial cyst compared with 32 (37%) patients treated with an index decompression and fusion procedure. Fifty-eight (68%) of the lumbar spinal cysts occurred at the L4-L5 level. There were 10 (11.5%) spinal synovial cyst recurrences in the decompression-only group, and 0 recurrences in the decompression/fusion group. Revision decompression procedures were performed in 4 of the 10 (4.6%) recurrences, and 6 of 10 (6.9%) recurrences had subsequent decompression and fusion surgery. The mean time to recurrence was 23.9±17.3 months. The mean length of follow-up was 65.1±48.6 months. Both recurrence and nonrecurrence cohorts had significant symptomatic improvement using Odom criteria.

CONCLUSIONS

Decompression and cyst excision was the more common surgical treatment of lumbar spinal synovial cysts compared with decompression/fusion procedure in our study. The rate of synovial cyst recurrence and revision surgery in patients undergoing index decompression was relatively low and comparable to current literature. Symptomatic improvement of patients undergoing decompression versus decompression/fusion was similar in our study. Although the fusion may be required for the extent of pathology or coexisting instability, decompression and excision of spinal synovial cysts provide durable, effective treatment with a known, appropriate risk of recurrence and subsequent revision surgery.

Surgical treatment of cervical subaxial intraspinal extradural cysts using a full-endoscopic uniportal posterior approach

PURPOSE

Symptomatic intraspinal extradural cysts of the cervical subaxial spine are rare, but usually require surgery. Conventional posterior decompression is the gold standard. However, there is increasing experience with endoscopic surgical techniques. The purpose of the study is to evaluate the technical implementation and outcomes of a full-endoscopic uniportal technique via the posterior approach in patients with symptomatic intraspinal extradural cysts of the cervical subaxial spine.

METHODS

Seven consecutive patients with a subaxial location of symptomatic intraspinal extradural cysts were decompressed in a full-endoscopic uniportal technique via the posterior approach between 2009 and 2015. Imaging and clinical data were collected in follow-up examinations for 18 months.

RESULTS

In all cases, the cyst was completely removed and adequate decompression was achieved using the full-endoscopic uniportal technique. One patient developed a dural leak that was sutured and covered intraoperatively. No other complications requiring treatment were observed. All patients had a good clinical outcome with stable regression of the radicular and central nerve pain or neurological deficits. The imaging follow-up showed sufficient decompression in all cases. No evidence was found of increasing instability during the follow-up period.

CONCLUSION

The full-endoscopic uniportal operation with a posterior approach allows the resection of the cyst and can minimize trauma and destabilization and has technical benefits and a low complication rate. It is an alternative surgical method that can offer advantages and is considered by the authors to be the surgical technique of choice for cervical subaxial intraspinal extradural cysts.

Resolution of Symptomatic Lumbar Synovial Cyst After Traumatic Event

BACKGROUND

Synovial cysts are most commonly found in the lumbar spine and are associated with low back pain and radiculopathy. Frequent use of imaging modalities has led to an increase in intraspinal synovial cyst identification. Treatment typically ranges from conservative measures to surgical decompression, but spontaneous resolution has previously been reported. Here, we present the first report of symptomatic lumbar synovial cyst resolution after a traumatic fall.

CASE DESCRIPTION

We present a case of a symptomatic synovial cyst between the fourth (L4) and fifth (L5) lumbar vertebrae identified on magnetic resonance imaging (MRI). The patient presented with right paramedian back pain and right-sided L5 radiculopathy. She underwent unsuccessful trials of antiinflammatory agents and physical therapy. Less than 1 year since initial diagnosis, the patient sustained a mechanic fall followed by resolution of prior symptoms. A subsequent lumbar MRI revealed complete resolution of the intraspinal synovial cyst.

CONCLUSIONS

The diagnosis of synovial cysts are increasing in frequency due to their ease of identification with computed tomography and MRI. For cases of refractory pain and/or neurologic deficits, surgical decompression is usually necessary. In rare instances, synovial cysts may spontaneously regress or resolve secondary to other events. This is the first description of resolution after a traumatic fall. Due to limited data on this topic, this report may provide additional insight into the pathophysiology of synovial cyst formation and resolution.

Stable Spondylolisthesis: Should Management Change Based on Presence of Facet Cysts?

STUDY DESIGN

This is a retrospective cohort review.

OBJECTIVE

To determine whether a correlation exists between facet cysts and lumbar instability.

SUMMARY OF BACKGROUND DATA

Lumbar facet cysts are common degenerative entities observed in patients with low-grade spondylolisthesis at a rate of 10%-50%. Surgical management with partial facetectomy with or without fusion remains controversial.

METHODS

Review of 86 patients with lumbar degenerative spondylolisthesis is performed. Preoperative magnetic resonance imagings were reviewed for the presence of lumbar facet cysts and Facet Fluid Indices (FFI)-calculated as the ratio of facet fluid width to facet width. Instability was defined as a difference of >3 mm in vertebral displacement between flexion and extension radiographs. T tests and the Pearson correlation analyses were used to determine statistical significance.

RESULTS

In total, 26 patients had unstable and 60 had stable spondylolisthesis. Facet cysts were present at an overall prevalence of 30.1%-in 10/26 patients in the unstable group and in 18/60 patients in the stable group (P>0.05). The average FFIs for the unstable and stable groups were 0.13 and 0.09, respectively (P>0.05). FFI in patients with facet cysts was significantly higher than those without (P<0.05). In addition, the group with facet cysts had a significantly higher proportion of patients with FF effusions >3 mm.

CONCLUSIONS

Lack of correlation with instability hints that the presence of facet cysts may not indicate instability in lumbar degenerative spondylolisthesis. Therefore, presence of facet cysts in static magnetic resonance imaging revealing spondylolisthesis should not preclude the physician from performing dynamic films to evaluate for instability. Significantly higher FFI in patients with facet cysts reaffirms the degenerative pathophysiology involved in their formation. Although this is not an outcomes study, it does spark interest into whether patients with stable spondylolisthesis and concurrent facet cysts are suitable for partial facetectomy alone with fusion.

Interlaminar stabilization and decompression for the treatment of bilateral juxtafacet cysts: Case report and literature review

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Lumbar juxtafacet cysts are typically treated by resection alone or resection combined with posterior instrumentation.

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Resection with instrumentation is associated with a lower rate of recurrence but also with increased cost and morbidity.

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We present a case of bilateral juxtafacet cysts causing neurogenic claudication treated with decompression and interlaminar stabilization.

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Complete symptom resolution was sustained at one-year follow-up.

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Decompression followed by interlaminar stabilization may be a reasonable alternative for some patients.

Introduction

Lumbar juxtafacet cysts (JFCs) are a common cause of lumbar radiculopathy which tend to occur in areas of increased facet mobility. While resection alone is a possible treatment, recent publications suggest that laminectomy alone for JFCs may not yield as favorable an outcome as laminotomies reinforced with posterior dynamic hardware. The Coflex^® is a novel interlaminar stabilization device that has been shown to achieve comparable results to rigid fusion in the management of lumbar stenosis in patients with no more than grade one anterolisthesis, and superior performance compared to laminectomy alone when a combined outcome score was used. We describe the combined use of dynamic posterior element fusion with primary cyst resection in the management of bilateral JFCs.

Presentation of case

A 71-year-old man who developed a progressive left L4 radiculopathy along with new urinary incontinence was found to have bilateral L3/4 JFCs causing significant lumbar stenosis and neurogenic claudication. After treatment with primary cyst resection and interlaminar stabilization, the patient experienced complete symptom resolution and was discharged to inpatient-rehabilitation on post-operative day 1.

Discussion

While current recommendations for the management of juxtafacet cysts causing progressive neurologic symptoms include surgical cyst removal and lumbar decompression with or without fusion, the role of dynamic interlaminar stabilization has not been explored.

Conclusion

Direct decompression followed by interlaminar stabilization may represent an alternative for patients to simultaneously benefit from a decompression of their juxtafacet cysts while affording posterior element reconstruction.

PERIARTICULAR CYSTS OF FACET JOINTS: ETIOPATHOGENESIS, DIAGNOSIS, METHODS OF SURGICAL TREATMENT. A CLINICAL EXAMPLE

Background. Periarticular cysts (PC) of facet joints is a rare pathology in neurosurgical practice. The concept of PC is applicable for all cysts that are located either pararticularly in the region of facet joints, or start from them.

Material and methods. A systematic search was performed in medical databases: Medline, RINC, EMedicine, UMKB, Pubmed on the relevant topic in Russian and English. The search query includes  words: arcuate joint, periarticular cyst, clinic, diagnosis, surgical  treatment. One of the significant factors of PC development is the  instability of the vertebralmotor segment of both degenerative and post-traumatic character.

Results. The result of the literature review was the writing of a clinical lecture, the current state of the issue of etiopathogenesis, diagnosis and management of patients with  periarticular cysts of facet joints was studied. The article gives a  clinical example of surgical treatment of a patient with a periarticular cyst at the level of LIV-LV on the right.

Conclusion. Periarticular cysts of facet joints are one of the factors of compression of cauda equina roots, with surgical treatment being  a radical and effective way of treatment. A detailed study of this  pathology is a promising direction in spinal neurosurgery. Further  research is required on comparative analysis of clinical and  instrumental efficacy of various methods of surgical treatment of periarticular cysts of facet joints.

The Prevalence of Incidental and Symptomatic Lumbar Synovial Facet Cysts

STUDY DESIGN

This was a retrospective cohort study from 2 affiliated tertiary care referral centers for spine disease.

OBJECTIVE

The purpose of this article was to assess the prevalence of incidental (ie, asymptomatic) and symptomatic lumbar synovial facet cysts on magnetic resonance imaging. Secondarily, we assessed whether the prevalence increases with age. In addition, we assessed differences in patient and cyst characteristics between asymptomatic and symptomatic facet cysts.

SUMMARY OF BACKGROUND

The prevalence of symptomatic and asymptomatic synovial facet cysts in the lumbar spine has been incompletely established, and, although many studies demonstrate an association with degenerative spine disease, no cumulative increase in prevalence of synovial facet cysts with increasing age has been presented.

METHODS

We included 19,010 consecutive patients who underwent a dedicated lumbar spine magnetic resonance imaging between 2004 and 2015. Our outcome measures were symptomatic and asymptomatic facet cysts. A symptomatic cyst was defined as a cyst with symptoms of radiculopathy on the same side as the cyst.

RESULTS

The overall synovial facet cyst prevalence was 6.5% [95% confidence interval (CI), 6.1-6.8]; 46% of the facet cysts were incidental and 54% were symptomatic. Increased age was independently associated with a higher likelihood of having a synovial facet cyst [odds ratio (per 10 y), 1.24, 95% CI, 1.20-1.29; P<0.001]. Large cyst size (odds ratio, 1.64; 95% CI, 1.23-2.20; P=0.001) and anterior location (odds ratio, 1.39; 95% CI, 1.08-1.79; P=0.010) of the synovial facet cyst were the only factors independently associated with having radiculopathy.

CONCLUSIONS

Approximately 1 in 15 patients have at least 1 synovial facet cyst. Having a facet cyst-symptomatic and asymptomatic-is strongly associated with increased age supporting the theory that degenerative disease underlies its development. Large cyst size and anterior location of the cyst are associated with an increased likelihood of having neurological symptoms.

LEVEL OF EVIDENCE

Level III, diagnostic study.

NeuroSpine Surgery Research Group (NSURG) Classification System for Grading Lumbar Synovial Cysts

To classify facet joint cysts (FJC) which will assist in identification of patient groups to best fit with a particular intervention. Sagittal T₂ -weighted magnetic resonance images (MRI) of these patients are used to measure cyst size, while axial T₂ -weighted MRI are used to determine the percentage of the vertebral canal occupied by the cyst. The degree of spondylolisthesis is also measured through standing X-rays or sagittal MRI. The proposed grading system is as follows. Grade I includes cysts that occupy less than 25% of the canal diameter that usually present with unilateral radiculopathy. Grade II includes cysts that occupy less than 50% of the canal diameter and may present with radiculopathy, with or without claudicant symptoms. Grade III cysts may present with radiculopathy and claudication with bilateral leg symptoms, along with facetogenic pain symptoms. Grades IV and V include potential instability as defined by greater than 15% spondylolisthesis in addition to either less than or greater than 50% canal stenosis. With higher grade cysts, presentation may include: facetogenic back pain, radiculopathy and claudicant pain in variable degrees of severity. The optimal classification system grades FJC from I to V on the basis of canal compression and degree of spondylolisthesis. Prospective studies are required to confirm the validity of this grading scale for long-term use.

Comparison of Decompression With and Without Fusion for Patients With Synovial Facet Cysts

STUDY DESIGN

This is a retrospective study.

OBJECTIVE

To compare (1) recurrence of radiculopathy and (2) back pain after decompression with and without fusion for patients with a symptomatic synovial cyst.

BACKGROUND

Previous work described favorable outcomes following cyst excision with and without fusion. Because of the association of facet cysts with spinal instability it is hypothesized that a decompression with fusion will lead to better outcomes. However, previous studies present contradicting results.

METHODS

We included 314 consecutive patients that underwent operative treatment for a facet cyst between 2003 and 2013 at 2 tertiary spine referral centers: 224 (71%) underwent decompression without fusion (35% spondylolisthesis), 90 (29%) underwent decompression with fusion (63% spondylolisthesis). Baseline data were compared between the groups. Bivariate log-rank analysis was used to compare outcomes between groups, followed by multivariable Cox regression analysis accounting for differences in baseline characteristics.

RESULTS

Patients undergoing decompression with fusion presented with a higher incidence of back pain (P=0.004) and spondylolisthesis (P<0.001), had more often bilateral decompressions (P<0.001), more facetectomies (P<0.001), and more levels of decompression (P=0.004) than those who underwent decompression alone. We found a difference in recurrence of radiculopathy (no fusion: 25% vs. fusion: 9.4%, P=0.029) in bivariate analysis. However, this difference did not hold when accounting for confounders (hazard ratio, 0.50, 95% confidence interval, 0.19-1.31, P=0.16). There was no difference in recurrence of back pain in bivariate (no fusion: 29% vs. fusion: 22%, P=0.51) and multivariable analysis (hazard ratio 0.51, 95% confidence interval, 0.23-1.14, P=0.10).

CONCLUSIONS

We found, with the numbers evaluated, no difference in recurrence of radiculopathy or back pain between patients undergoing decompression with or without fusion after accounting for confounders. The decision for fusion should be considered in light of the extent of decompression and the existence of other pathology.

LEVEL OF EVIDENCE

Level III-therapeutic study.

Long-Term Effectiveness of Direct CT-Guided Aspiration and Fenestration of Symptomatic Lumbar Facet Synovial Cysts

BACKGROUND AND PURPOSE

Lumbar facet synovial cysts are commonly seen in facet degenerative arthropathy and may be symptomatic when narrowing the spinal canal or compressing nerve roots. The purpose of this study was to analyze the safety, effectiveness, and long-term outcomes of direct CT-guided lumbar facet synovial cyst aspiration and fenestration for symptom relief and for obviating an operation.

MATERIALS AND METHODS

We retrospectively reviewed the medical records and imaging studies of 64 consecutive patients between 2006 and 2016 who underwent 85 CT-guided lumbar facet synovial cyst fenestration procedures in our department. We recorded patient demographics, lumbar facet synovial cyst imaging characteristics, presenting symptoms, change in symptoms after the procedure, and whether they underwent a subsequent operation. We also assessed long-term outcomes from the medical records and via follow-up telephone surveys with patients.

RESULTS

Direct CT-guided lumbar facet synovial cyst puncture was technically successful in 98% of procedures. At first postprocedural follow-up, 86% of patients had a complete or partial symptomatic response. During a mean follow-up of 49 months, 56% of patients had partial or complete long-term relief without the need for an operation; 44% of patients underwent an operation. Patients with calcified, thick-rimmed, or low T2 signal intensity cysts were less likely to respond to the procedure and more likely to need an operation.

CONCLUSIONS

CT-guided direct lumbar facet synovial cyst aspiration and fenestration procedures are safe, effective, and minimally invasive for symptomatic treatment of lumbar synovial facet cysts. This procedure obviates an operation in a substantial number of patients, even at long-term follow-up, and should be considered before surgical intervention.

Lumbar ganglion cyst: Nosology, surgical management and proposal of a new classification based on 34 personal cases and literature review

AIM

To analyze different terms used in literature to identify lumbar extradural cysts and propose a common scientific terminology; to elaborate a new morphological classification of this pathology, useful for clinical and surgical purposes; and to describe the best surgical approach to remove these cysts, in order to avoid iatrogenic instability or treat the pre-existing one.

METHODS

We retrospectively reviewed 34 patients with symptomatic lumbar ganglion cysts treated with spinal canal decompression with or without spinal fixation. Microsurgical approach was the main procedure and spinal instrumentation was required only in case of evident pre-operative segmental instability.

RESULTS

The complete cystectomy with histological examination was performed in all cases. All patients presented an improvement of clinical conditions, evaluated by Visual Analogic Scale and Japanese Orthopaedic Association scoring.

CONCLUSION

Spinal ganglion cysts are generally found in the lumbar spine. The treatment of choice is the microsurgical cystectomy, which generally does not require stabilization. The need for fusion must be carefully evaluated: Pre-operative spondylolisthesis or a wide joint resection, during the operation, are the main indications for spinal instrumentation. We propose the terms “ganglion cyst” to finally identify this spinal pathology and for the first time its morphological classification, clinically useful for all specialists.

Thoracic Synovial Cyst at the Th2-3 Level Causing Myelopathy

Intraspinal synovial cyst is a rare cause of myelopathy. These cysts present most often in the lumbar and cervical parts of the spine but are more infrequent in the thoracic spine. We present a case of a 73-year-old man with an intraspinal, extradural synovial cyst at the Th2-3 level causing paraesthesia and weakness in the legs. A laminectomy and excision of the cyst were performed and the patient recovered fully. In the thoracic spine, synovial cysts are almost exclusively found in the lower part. Laminectomy, with excision, is the treatment of choice, although steroid injections have been described.

Synovial cysts of the spine: long-term follow-up after surgical treatment of 141 cases in a single-center series and comprehensive literature review of 2900 degenerative spinal cysts

OBJECTIVE Synovial cysts of the spine are rare lesions, predominantly arising in the lumbar region. Despite their generally benign behavior, they can cause severe symptoms due to compression of neural structures in the spinal canal. Treatment strategies are still a matter of discussion. The authors performed a single-center survey and literature search focusing on long-term results after minimally invasive surgery. METHODS A total of 141 consecutive patients treated for synovial cysts of the lumbar spine between 1997 and 2014 in the authors' department were analyzed. Medical reports with regard to signs and symptoms, operative findings, complications, and short-term outcome were reviewed. Assessment of long-term outcome was performed with a standardized telephone questionnaire based on the Oswestry Disability Index (ODI). Furthermore, patients were questioned about persisting pain, symptoms, and further operative procedures, if any. Subjective satisfaction was classified as excellent, good, fair, or poor based on the Macnab classification. RESULTS The approach most often used for synovial cyst treatment was partial hemilaminectomy in 70%; hemilaminectomy was necessary in 27%. At short-term follow-up, the presence of severe and moderate leg pain had decreased from 93% to 5%. The presence of low-back pain decreased from 90% to 5%. Rates of motor and sensory deficits were reduced from 40% to 14% and from 45% to 6%, respectively. The follow-up rate was 58%, and the mean follow-up period was 9.3 years. Both leg pain and low-back pain were still absent in 78%. Outcome based on the Macnab classification was excellent in 80%, good in 14%, fair in 1%, and poor in 5%. According to the ODI, 78% of patients had no or only minimal disability, 16% had moderate disability, and 6% had severe disability at the time of follow-up. In this cohort, 7% needed surgery due to cyst recurrence, and 9% required a delayed stabilization procedure after the initial operation. CONCLUSIONS Surgical treatment with resection of the cyst provides favorable results in outcome. Excellent or good outcome persisting for a long-term follow-up period can be achieved in the vast majority of cases. Complication rates are low despite an increased risk of dural injury. With facet-sparing techniques, the stability of the segment can be preserved, and resection of spinal synovial cysts does not necessarily require segmental fusion.

Long-term outcomes of percutaneous lumbar facet synovial cyst rupture

OBJECTIVE

To evaluate the therapeutic value, safety, and long-term clinical outcomes of percutaneous lumbar facet synovial cyst (LFSC) rupture.

MATERIALS AND METHODS

Our study was institutional review board (IRB)-approved and Health Insurance Portability and Accountability Act (HIPAA)-compliant. The study group comprised 71 patients (44 women, mean age: 65 ± 17 years) who underwent CT- or fluoroscopy-guided percutaneous LFSC rupture. The technical success of LFSC rupture, the long-term clinical outcome, including repeat procedures or surgery, and imaging findings on MRI and CT were recorded.

RESULTS

Seventy-nine LFSC ruptures were performed in 71 patients. CT guidance was used in 57 cases and fluoroscopy guidance in 22 cases. LFSC rupture was technically successful in 58 out of 79 cases (73 %). Mean injection volume for cyst rupture was 3.6 ± 2.2 mL and a combination of steroid and anesthetic was injected in all cases. Over a mean follow-up time of 44 months, 12 % of patients underwent repeat cyst rupture, and 46 % eventually underwent surgery, whereas the majority of patients (55 %) experienced symptomatic relief and did not undergo surgery. There was no significant association between a successful outcome and age, sex, level, or size of LFSC (p > 0.1). LFSCs with T2 hypointensity were more likely to require surgery (p = 0.02). There was one complication, a bacterial skin infection that completely resolved following antibiotic therapy.

CONCLUSION

Percutaneous LFSC rupture is an effective and safe nonsurgical treatment option for LFSC. More than half of treated patients were able to avoid subsequent surgery. Therefore, percutaneous LFSC rupture should be considered before surgical intervention.

Association of Lumbar Synovial Cysts with Facet Effusion

To show the frequent association of synovial cysts and facet effusion.

MR studies of 26 patients with lumbar synovial cysts were reviewed for sex/age incidence, anatomic location, multiplicity of cysts and associated pathologies. All studies were reviewed for presence of facet effusion.

26 patients had 39 MRI documented synovial (17 females, 9 males). Age distribution: 41 – 79 years. Location of cysts: L4/5 = 29, L3/4 = 6, L5/S1 = 3, L1/2= −;1. 36 synovial cysts showed facet effusion. 19 patients also had facet effusions at adjoining motion segments or at contralateral joints. Synovial cysts were found in anterior (n=20), posterior (n=13), anterior-posterior (n=3) positions. 18 patients had cysts localized to one single facet joint, 8 patients showed synovial cysts at multiple facet joints.

The frequent coexistence of synovial cysts and facet effusion in our material suggests a causal relationship. External herniation of synovium from a fluid expanded joint space appears to be the most plausible pathologic mechanism.

Acquired Degenerative Changes of the Intervertebral Segments at and Supradjacent to the Lumbosacral Junction

In earlier evolutionary times, mammals were primarily quadrupeds, although other bipeds have been represented during the course of the Earth's several billion-year history. In many cases, either the bipedal stance yielded a large tail and hypoplastic upper extremities (e.g., Tyrannosaurus rex, the kangaroo), or it culminated in hypoplasia of the tail and further development and specialization of the upper extremities (e.g., nonhuman primates and human beings). In the human species this relatively recently acquired posture resulted in a more or less pronounced lumbosacral lordosis. In turn, certain compensatory anatomic features have since occurred. These include the normal characteristic posteriorly directed wedge-shape of the L5 vertebral body and the L5-S1 intervertebral disc; the L4 vertebral body and the L4-L5 and L3-4 disc may be similarly visibly affected.

These compensatory mechanisms, however, have proved to be functionally inadequate over the present long-term of the human life span. Upright posture leads to increased weight bearing in humans that progressively causes excess stresses at and suprajacent to the lumbosacral junction. These combined factors result in accelerated aging and degenerative changes and a predisposition to frank biomechanical failure of the subcomponents of the spinal column in these spinal segments.

One other specific problem that occurs at the lumbosacral junction that predisposes toward premature degeneration is the singular relationship that exists between a normally mobile segment of spine (i.e., the lumbar spine), and a normally immobile one (i.e., the sacrum). It is well known that mobile spinal segments adjacent to congenitally or acquired fused segments have a predilection toward accelerated degenerative changes. The only segment of the spine in which this is invariably normally true is at the lumbosacral junction (i.e., the unfused lumbar spine adjoining the fused sacrum).

Nevertheless, biomechanical failures of the human spine are not lethal traits; in most cases today, mankind reaches sexual maturity before spinal biomechanical failure precludes sexual reproduction. For this gene-preserving reason, degenerative spinal disorders will likely be a part of modern societies for the foreseeable eternity of the race.

The detailed alterations accruing from the interrelated consequences of and phenomena contributing to acquired degenerative changes of the lumbosacral intervertebral segments as detailed in this discussion highlight the extraordinary problems that are associated with degenerative disease in this region of the spine. Further clinicoradiologic research in this area will progressively determine the clinical applications and clinical efficacy of the various traditional and newer methods of therapy in patients presenting with symptomatic acquired collapse of the intervertebral discs at and suprajacent to the lumbosacral junction and the interrelated degenerative alterations of the nondiscal structures of the spine.

Contralateral Juxtafacet Cyst Development after the Spontaneous Resolution of a Previous Facet Cyst

Juxtafacet cysts are implicated in neural compression. Thus far, it is known that surgical removal is the definitive treatment for symptomatic juxtafacet cyst because spontaneous regression is rare, and the failure rate of conservative treatment is high. We have reported a rare case of right-sided juxtafacet cyst development after the spontaneous resolution of contralateral left-sided facet cyst. The left-sided facet cyst resolved spontaneously without surgical treatment, but a juxtacyst developed on the contralateral facet on the right side, as illustrated on 4-year follow-up magnetic resonance images. To the best of our knowledge, this is the first report of newly developed contralateral juxtafacet cyst after spontaneous regression. Herein, we have discussed the natural history and the management of this rare case.

Cystic Abnormalities of the Spinal Cord and Vertebral Column

Cystic lesions of the vertebral column and spinal cord are important differential diagnoses in dogs with signs of spinal cord disease. Synovial cysts are commonly associated with degenerative joint disease and usually affect the cervical and lumbosacral regions. Arachnoid diverticulum (previously known as cyst) is seen in the cervical region of large breed dogs and thoracolumbar region of small breed dogs. This article reviews the causes, diagnosis, and treatment of these and other, less common, cystic lesions.

Epiduroscopic Removal of a Lumbar Facet Joint Cyst

Facet joint synovial cysts are usually associated with osteoarthritis of the adjacent facet joint and/or spondylolisthesis. In between the conservative and operative ends of the treatment spectrum lie minimally invasive techniques such as cyst rupture using epiduroscopy. In this report, we describe an 82-year-old male patient presenting with low back pain radiating to his lower left extremity and associated paresthesia. Magnetic resonance imaging of the lumbar spine revealed a synovial cyst at left L4/5 facet joint. Using epiduroscopy, the cyst was mechanically ruptured by popping it with the tip of the scope. The patient remained symptom-free at his successive visits until 12 months after the procedure, and was opened for desired follow up.

Minimally invasive resection of lumbar intraspinal synovial cysts via a contralateral approach: review of 13 cases

OBJECT

The authors sought to determine patient-related outcomes after minimally invasive surgical (MIS) lumbar intraspinal synovial cyst excision via a tubular working channel and a contralateral facet-sparing approach.

METHODS

All the patients with a symptomatic lumbar intraspinal synovial cyst who underwent surgery at the University of Iowa Hospitals and Clinics with an MIS excision via a contralateral approach were treated between July 2010 and August 2014. There was a total of 13 cases. Each patient was evaluated with preoperative neurological examinations, lumbar spine radiography, MRI, and visual analog scale (VAS) scores. The patients were evaluated postoperatively with neurological examinations and VAS and Macnab scores. The primary outcomes were improvement in VAS and Macnab scores. Secondary outcomes were average blood loss, hospital stay duration, and operative times.

RESULTS

There were 5 males and 8 females. The mean age was 66 years, and the mean body mass index was 28.5 kg/m2. Sixty-nine percent (9 of 13) of the cysts were at L4–5. Most patients had low-back pain and radicular pain, and one-third of them had Grade 1 spondylolisthesis. The mean (± SD) follow-up duration was 20.8 ± 16.9 months. The mean Macnab score was 3.4 ± 1.0, and the VAS score decreased from 7.8 preoperatively to 2.9 postoperatively. The mean operative time was 123 ± 30 minutes, with a mean estimated blood loss of 44 ± 29 ml. Hospital stay averaged 1.5 ± 0.7 days. There were no complications noted in this series.

CONCLUSIONS

The MIS excision of lumbar intraspinal synovial cysts via a contralateral approach offers excellent exposure to the cyst and spares the facet joint at the involved level, thus minimizing risk of instability, blood loss, operative time, and hospital stay. Prospective randomized trials with longer follow-up times and larger cohorts are needed to conclusively determine the superiority of the contralateral MIS approach over others, including open or ipsilateral minimally invasive surgery.

Lumbosacral intraspinal extradural ganglion cyst in a cat

Case summary

A 16-year-old neutered female domestic shorthair cat was referred for chronic history of reluctance to jump, stiffness of the tail and lower back pain. Mild pelvic limb ataxia, reduced perianal reflex and lumbosacral discomfort were present on neurological examination. On magnetic resonance imaging, a well-defined rounded structure of 3 mm in diameter was identified on the right dorsal aspect of the epidural space at L7–S1, causing displacement of the cauda equina. The lesion was hyperintense to spinal cord parenchyma on T2-weighted images and hypointense on T1-weighted images, consistent with a fluid-filled structure. A Lumbosacral dorsal laminectomy was performed. A clear fluid-containing structure was identified between the right L7 nerve root and the cauda equina. Following surgical excision, histopathology confirmed the cystic nature of the lesion and revealed thick disorganised sheaths of fibrocollagenous tissue and flattened mesenchymal cells lining the luminal part of the cyst wall. A diagnosis of intraspinal ganglion cyst was made. The cat recovered uneventfully. Seven months after surgery euthanasia was performed for unrelated reasons; no neurological deficits were present.

Relevance and novel information

This is the first reported case of intraspinal ganglion cyst in a cat. Intraspinal extradural cysts should be considered among other differential diagnoses for cats with lumbosacral myelopathy/radiculopathy.

Haemorrhagic lumbar juxtafacet cyst with ligamentum flavum involvement

Juxtafacet cysts are an uncommon cause of radiculopathy. They occur most frequently in the lumbar region, and their distribution across the spine correlates with mobility. Haemorrhagic complications are rare and may occur in the absence of any provocation, although there is some association with anticoagulation and trauma. We present a case of acute radiculopathy due to an L5/S1 juxtafacet cyst with unprovoked haemorrhage which was found to extend into ligamentum flavum. The patient underwent uncomplicated microscope assisted decompression with excellent results. The demographics, presentation, aetiology, and management of juxtafacet cysts are discussed.

Acute myelopathy caused by a cervical synovial cyst

Synovial cysts of the cervical spine, although they occur infrequently, may cause acute radiculopathy or myelopathy. Here, we report a case of a cervical synovial cyst presenting as acute myelopathy after manual stretching. A 68-year-old man presented with gait disturbance, decreased touch senses, and increased sensitivity to pain below T12 level. These symptoms developed after manual stretching 3 days prior. Computed tomography scanning and magnetic resonance imaging revealed a 1-cm, small multilocular cystic lesion in the spinal canal with cord compression at the C7-T1 level. We performed a left partial laminectomy of C7 and T1 using a posterior approach and completely removed the cystic mass. Histological examination of the resected mass revealed fibrous tissue fragments with amorphous materials and granulation tissue compatible with a synovial cyst. The patient's symptoms resolved after surgery. We describe a case of acute myelopathy caused by a cervical synovial cyst that was treated by surgical excision. Although cervical synovial cysts are often associated with degenerative facet joints, clinicians should be aware of the possibility that these cysts can cause acute neurologic symptoms.

Lumbar intraforaminal synovial cyst in young adulthood: case report and review of the literature

Study Design Case report. Objective Lumbar juxtafacet cysts (synovial and ganglion cysts) are a rare cause of low back and radicular leg pain. Most patients with lumbar cysts are in their sixth decade of life and have significant facet joint and disk degeneration. Lumbar synovial cysts (LSCs) are extremely rare in adolescence and young adulthood, and to our knowledge, only two pediatric cases of LSC have been reported in the literature. We aim to prove the existence of LSC in adolescent patients as a real entity that causes low back and radicular complaints and to discuss the possibility of traumatic injury as a pathogenic cause of LSC formation in adolescence. A case of an 18-year old patient with LSC is presented. We report the clinical presentation, management, outcome, and review of the literature, focusing on issues that remain debatable. Methods The case is presented together with its clinical course, the diagnostic techniques, the surgical findings, histologic results, and the treatment outcome. Results After surgical treatment, the patient's complaints were alleviated and almost no complaints were registered during the next 6 months' follow-up. Conclusions LSCs are extremely rare in adolescence, but they could be considered in the differential diagnosis in adolescent patients with low back pain and radiculopathy. Surgical removal of LSC could be considered as a treatment option to provide immediate and safe symptomatic relief.

Ganglion cyst arising from the composite occipito-atlanto-axial joint cavity in a cat

A four-year-old, female spayed Domestic Longhaired cat was referred for evaluation with a two month history of initial inability to jump progressing to ambulatory tetraparesis. Magnetic resonance imaging studies demonstrated a cystic lesion arising from the composite occipito-atlanto-axial joint cavity and extending to the region of the occipital bone and the axis. The lesion surrounded the spinal canal, causing moderate dorsal spinal cord compression at the atlanto-occipital joint. A dynamic myelographic study demonstrated attenuation of the dorsal contrast column at the atlanto-occipital joint when the cervical spine was positioned in extension. Partial excision of the cyst capsule by a ventral approach resulted in long-term (64 months) resolution of clinical signs. Histological evaluation was consistent with a ganglion cyst. An intra-spinal ganglion cyst arising from the composite occipito-atlanto-axial joint cavity may be considered as an uncommon differential diagnosis for cats with cervical myelopathy.

Ligamentum flavum cyst of lumbar spine: a case report and literature review

Ligamentum flavum cysts have rarely been reported and known to be the uncommon cause of spinal compression and radiculopathy. A 63-year-old man presented right sciatica lasting for 1 month. Lumbar computerized tomography and magnetic resonance imaging demonstrated an extradural cystic mass adjacent to the L5-S1 facet joints. Partial hemilaminectomy and flavectomy at the L5-S1 space were performed, and then the cystic mass was excised. Histopathology confirmed a connective tissue cyst, which is consistent with the ligamentum flavum. Microscopic examination of the cyst wall revealed that it is closely packed collagen fibril. The symptom of patient was improved after surgery. Because of rarity of ligamentum flavum cysts and nonspecific clinical and radiologic findings, the preoperative diagnosis is not easy. The histologic features of ligamentum flavum cysts are distinct from other cystic lesion of lumbar spine. This study presents a case and literature review of ligamentum flavum cyst. We summarize the pathophysiology, occurrence, differential diagnosis of rare ligamentum flavum cyst, especially on lumbar spine.

Extramedullary spinal cysts in dogs

OBJECTIVE

To (1) synthesize the terminology used to classify extramedullary spinal cysts in dogs to clarify some of the commonly reported misconceptions, and (2) propose a classification scheme to limit confusion with terminology.

STUDY DESIGN

Literature review.

METHODS

An online bibliographic search was performed in January 2013 for articles relating to extramedullary spinal cysts in dogs using PubMed (http://www.pubmed.gov/) and Google Scholar (http://scholar.google.com/) databases. Only peer-reviewed clinical literature describing cystic lesions pertaining to the spinal cord and associated structures was included.

RESULTS

From 1962 to 2013, 42 articles were identified; 25 (95 dogs) reported meningeal cysts, 10 (24 dogs) described 60 extradural cysts, 3 reports (18 dogs) described discal cysts or acute compressive hydrated nucleus pulposus extrusions (HNPE). Spinal cysts were categorized by location based on cross-sectional imaging as meningeal or extradural non-meningeal. Sub-classification was then performed based on surgical findings and pathology. Meningeal cysts included arachnoid diverticulae and Tarlov (perineural) cysts. Extradural non-meningeal cysts included intraspinal cysts of the vertebral joints, ligaments and discs. Discal cysts also fit this category and have been reported extensively in humans but appear rare in dogs.

CONCLUSIONS

Extramedullary spinal cysts should be first classified according to location with a sub-classification according to pathologic and surgical findings. Previous canine cases of discal cysts appear to represent a different disease entity and the term acute compressive HNPE is therefore preferred.